<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script src="https://cdn.staticfile.org/vue/2.2.2/vue.min.js">

    </script>
</head>
<body>
<div id="header">{{score}}</div>
<script>
    var vm = new Vue({
        el: "#header",
        data: {
            score: 300
        }
    });
</script>
</body>
</html>